The gunman slain by police after he killed his English professor and eight others at an Oregon college was once turned away from a firearms academy by an instructor who recalled finding him “weird” and “a little bit too anxious” for high-level weapons training.

Christopher Harper-Mercer, 26, who moved to Oregon from the Los Angeles suburb of Torrance, California, was officially identified on Friday as the assailant in the rampage at Umpqua Community College in Roseburg, which ranks as the deadliest among dozens of U.S. mass shootings in the past two years.

According to accounts of survivors, the gunman stormed into the classroom of his introductory writing class to shoot the professor at point-blank range, then began picking off other victims one at a time as he questioned each about their religion and whether they were Christians................